[InstCombine] allow fmul-sqrt folds with less than full -ffast-math
Also, add a Builder method for intrinsics to reduce code duplication for clients.
llvm-svn: 325960
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp b/llvm/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp
index cb48b93..d5456cc 100644
--- a/llvm/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstCombineMulDivRem.cpp
@@ -662,24 +662,17 @@
}
}
- // sqrt(a) * sqrt(b) -> sqrt(a * b)
- if (AllowReassociate && Op0->hasOneUse() && Op1->hasOneUse()) {
- Value *Opnd0 = nullptr;
- Value *Opnd1 = nullptr;
- if (match(Op0, m_Intrinsic<Intrinsic::sqrt>(m_Value(Opnd0))) &&
- match(Op1, m_Intrinsic<Intrinsic::sqrt>(m_Value(Opnd1)))) {
- BuilderTy::FastMathFlagGuard Guard(Builder);
- Builder.setFastMathFlags(I.getFastMathFlags());
- Value *FMulVal = Builder.CreateFMul(Opnd0, Opnd1);
- Value *Sqrt = Intrinsic::getDeclaration(I.getModule(),
- Intrinsic::sqrt, I.getType());
- Value *SqrtCall = Builder.CreateCall(Sqrt, FMulVal);
- return replaceInstUsesWith(I, SqrtCall);
- }
+ // sqrt(X) * sqrt(Y) -> sqrt(X * Y)
+ Value *X, *Y;
+ if (I.hasAllowReassoc() &&
+ match(Op0, m_OneUse(m_Intrinsic<Intrinsic::sqrt>(m_Value(X)))) &&
+ match(Op1, m_OneUse(m_Intrinsic<Intrinsic::sqrt>(m_Value(Y))))) {
+ Value *XY = Builder.CreateFMulFMF(X, Y, &I);
+ Value *Sqrt = Builder.CreateIntrinsic(Intrinsic::sqrt, { XY }, &I);
+ return replaceInstUsesWith(I, Sqrt);
}
// -X * -Y --> X * Y
- Value *X, *Y;
if (match(Op0, m_FNeg(m_Value(X))) && match(Op1, m_FNeg(m_Value(Y))))
return BinaryOperator::CreateFMulFMF(X, Y, &I);